Evolutionary drivers of reproductive fitness in two endangered forest trees.

Population genetics theory predicts a relationship between fitness, genetic diversity (H0) and effective population size (Ne), which is often tested through heterozygosity-fitness correlations (HFCs). We tested whether population and individual fertility and heterozygosity are correlated in two endangered Mexican spruces (Picea martinezii and Picea mexicana) by combining genomic, demographic and reproductive data (seed development and germination traits). For both species, there was a positive correlation between population size and seed development traits, but not germination rate. Individual genome-wide heterozygosity and seed traits were only correlated in P. martinezii (general-effects HFC), and none of the candidate single nucleotide polymorphisms (SNPs) associated with individual fertility showed heterozygote advantage in any species (no local-effects HFC). We observed a single and recent (c. 30 thousand years ago (ka)) population decline for P. martinezii; the collapse of P. mexicana occurred in two phases separated by a long period of stability (c. 800 ka). Recruitment always contributed more to total population census than adult trees in P. mexicana, while this was only the case in the largest populations of P. martinezii. Equating fitness to either H0 or Ne, as traditionally proposed in conservation biology, might not always be adequate, as species-specific evolutionary factors can decouple the expected correlation between these parameters.

Quantifying long-term phenological patterns of aerial insectivores roosting in the Great Lakes region using weather surveillance radar.

Organisms have been shifting their timing of life history events (phenology) in response to changes in the emergence of resources induced by climate change. Yet understanding these patterns at large scales and across long time series is often challenging. Here we used the US weather surveillance radar network to collect data on the timing of communal swallow and martin roosts and evaluate the scale of phenological shifts and its potential association with temperature. The discrete morning departures of these aggregated aerial insectivores from ground-based roosting locations are detected by radars around sunrise. For the first time, we applied a machine learning algorithm to automatically detect and track these large-scale behaviors. We used 21 years of data from 12 weather surveillance radar stations in the Great Lakes region to quantify the phenology in roosting behavior of aerial insectivores at three spatial levels: local roost cluster, radar station, and across the Great Lakes region. We show that their peak roosting activity timing has advanced by 2.26 days per decade at the regional scale. Similar signals of advancement were found at the station scale, but not at the local roost cluster scale. Air temperature trends in the Great Lakes region during the active roosting period were predictive of later stages of roosting phenology trends (75% and 90% passage dates). Our study represents one of the longest-term broad-scale phenology examinations of avian aerial insectivore species responding to environmental change and provides a stepping stone for examining potential phenological mismatches across trophic levels at broad spatial scales.

Demographic modelling helps track the rapid and recent divergence of a conifer species pair from Central Mexico.

Secondary contact of recently diverged species may have several outcomes, ranging from rampant hybridization to reinforced reproductive isolation. In plants, selfing tolerance and disjunct reproductive phenology may lead to reproductive isolation at contact zones. However, they may also evolve under both allopatric or parapatric frameworks and originate from adaptive and/or neutral forces. Inferring the historical demography of diverging taxa is thus a crucial step to identify factors that may have led to putative reproductive isolation. We explored various competing demographypotheses to account for the rapid divergence of a fir species complex (Abies flinckii-A. religiosa) distributed in "sky-islands" across central Mexico (i.e., along the Trans-Mexican Volcanic Belt; TMVB). Despite co-occurring in two independent sympatric regions (west and centre), these taxa rarely interbreed because of disjunct reproductive phenologies. We genotyped 1147 single nucleotide polymorphisms, generated by GBS (genotyping by sequencing), across 23 populations, and compared multiple scenarios based on the geological history of the TMVB. The best-fitting model revealed one of the most rapid and complete speciation cases for a conifer species-pair, dating back to ~1.2 million years ago. Coupled with the lack of support for stepwise colonization, our coalescent inferences point to an early cessation of interspecific gene flow under parapatric speciation; ancestral gene flow during divergence was asymmetrical (mostly from western firs into A. religiosa) and exclusive to the most ancient (i.e., central) contact zone. Factors promoting rapid reproductive isolation should be explored in other slowly evolving species complexes as they may account for the large tropical and subtropical diversity.

Decoupling the adsorption mechanisms of arsenate at molecular level on modified cube-shaped sponge loaded superparamagnetic iron oxide nanoparticles.

In this study, a commercial cube-shaped open-celled cellulose sponge adsorbent was modified by in-situ co-precipitation of superparamagnetic iron oxide nanoparticles (SPION) and used to remove As(V) from aqueous solutions. Fe K-edge X-ray absorption spectroscopy (XAS) and TEM identified maghemite as the main iron phase of the SPION nanoparticles with an average size 13 nm. Batch adsorption experiments at 800 mg/L showed a 63% increase of adsorption capacity when loading 2.6 wt.% mass fraction of SPION in the cube-sponge. Experimental determination of the adsorption thermodynamic parameters indicated that the As(V) adsorption on the composite material is a spontaneous and exothermic process. As K-edge XAS results confirmed that the adsorption enhancement on the composite can be attributed to the nanoparticles loaded. In addition, adsorbed As(V) did not get reduced to more toxic As(III) and formed a binuclear corner-sharing complex with SPION. The advantageous cube-shape of the sponge-loaded SPION composite together with its high affinity and good adsorption capacity for As(V), good regeneration capability and the enhanced-diffusion attributed to its open-celled structure make this adsorbent a good candidate for industrial applications.

Assessment of anthelmintic effectiveness to control Fasciola hepatica and paramphistome mixed infection in cattle in the humid tropics of Mexico.

The objective of this study was to evaluate the effectiveness of the main anthelmintics used for the control of trematodes in cattle in an endemic area in the humid Mexican tropics. A diagnostic study was carried out in nine cattle farms to determine the prevalence of flukes through faecal examination. Only three farms with more than 20 cows positive to trematodes were chosen to determine the effectiveness of commercial anthelmintics (triclabendazole, TCBZ; ivermectin + closantel, (IVM + CLOS); IVM + clorsulon, (CLORS); nitroxynil, NITROX). The prevalence of Fasciola hepatica was 27.1% and 29.6% of paramphistomes. The faecal egg count of trematodes ranged from 0.0 to 12.2 eggs per gram of faeces. The highest effectiveness against F. hepatica was 96.7%, and 92.7% against paramphistomes. NITROX was the most effective in the control of trematodes, while other products, such as IVM + CLORS and TCBZ obtained values lower than 90%, which puts sustainable trematode control at risk. The presence of trematodes was observed on most farms, although the prevalence per herd was highly variable, which indicates that the trematodes F. hepatica and paramphistomes are endemic to the region and a suitable management programme is suggested to control infections caused by these parasites.

[Consensus statement of the Chilean endocrinological society on the role of bariatric surgery in type 2 diabetes]. / Rol de la cirugía bariátrica/metabólica en el manejo de la diabetes mellitus 2. Consenso SOCHED/SCCBM.

Diabetes Mellitus (DM) and obesity are a public health problem in Chile. Bariatric surgery is the most effective treatment alternative to achieve a significant and sustained weight reduction in patients with morbid obesity. The results of controlled clinical trials indicate that, compared to medical treatment, surgery for obese patients with DM2 allows a better control of blood glucose and cardiovascular risk factors, reduces the need for medications and increases the likelihood for remission. Consensus conferences and clinical practice guidelines support bariatric surgery as an option to treat DM2 in Class III Obesity (Body Mass Index (BMI) > 40) regardless of the glycemic control and the complexity of pharmacological treatment and in Class II Obesity (BMI 35-39,9) with inadequate glycemic control despite optimal pharmacological treatment and lifestyle. However, surgical indication for patients with DM2 and BMI between 30-34.9, the most prevalent sub-group, is only suggested. The Chilean Societies of Endocrinology and Diabetes and of Bariatric and Metabolic Surgery decided to generate a consensus regarding the importance of other factors related to DM2 that would allow a better selection of candidates for surgery, particularly when weight does not constitute an indication. Considering the national reality, we also need a statement regarding the selection and characteristics of the surgical procedure as well as the role of the diabetologist in the multidisciplinary team.

A preliminary study of gut dysbiosis in children with food allergy.

Gut microbiota of food allergic children was analyzed by high throughput 16S rRNA gene sequencing. Signs of gut dysbiosis, which is likely associated with gut inflammation, was observed in children with food allergies. For example, decreased abundance of genus Akkermansia but increased abundance of Veillonella was found in children with food allergy in comparison with healthy control children.

A pore forming peptide from spider Lachesana sp. venom induced neuronal depolarization and pain.

BACKGROUND: Arachnoid venoms contain numerous peptides with ion channel modifying and cytolytic activities. METHODS: We developed a green fluorescent protein (GFP)-based assay that can monitor the changes in currents through overexpressed inwardly rectifying K(+) channels (Kir2.1), in which GFP expression was increased by blockade of Kir2.1 current. Using this assay, we screened venom of many spider species. A peptide causing GFP decreasing effect was purified and sequenced. Electrophysiological and pain-inducing effects of the peptide were analyzed with whole-cell patch-clamp recordings and hot-plate test, respectively. RESULTS: Among venoms we screened, soluble venom from Lachesana sp. decreased the GFP expression. Purification and sequencing of the peptide showed that the peptide is identical to a pore-forming peptide purified from Lachesana tarabaevi venom. Whole cell patch-clamp recordings revealed that the peptide had no effect on Kir2.1 current. Instead, it induced a current that was attributable to the pore-formation of the peptide. The peptide was selectively incorporated into hyperpolarized, i.e., Kir2.1 expressing, cells and for this reason the peptide decreased GFP expression in our Kir2.1 assay. The pore-formation positively shifted the reversal potential and induced burst firings in the hippocampal neurons in a synaptic current-independent way. The application of the Lachesana sp. peptide induced pain-related behavior in mice. CONCLUSIONS: The peptide, which was found in Lachesana sp. venom, formed pores and thereby depolarized neurons and induced pain. GENERAL SIGNIFICANCE: Our data suggested an additional physiological role of the pore-forming peptides.

Evaluation of the short- and long-term effectiveness and safety of fully covered self-expandable metal stents for drainage of pancreatic fluid collections: results of a Spanish nationwide registry.

BACKGROUND AND AIMS: Initial reports suggest that fully covered self-expandable metal stents (FCSEMSs) may be better suited for drainage of dense pancreatic fluid collections (PFCs), such as walled-off pancreatic necrosis. The primary aim was to analyze the effectiveness and safety of FCSEMSs for drainage of different types of PFCs in a large cohort. The secondary aim was to investigate which type of FCSEMS is superior. METHODS: This was a retrospective, noncomparative review of a nationwide database involving all hospitals in Spain performing EUS-guided PFC drainage. From April 2008 to August 2013, all patients undergoing PFC drainage with an FCSEMS were included in a database. The main outcome measurements were technical success, short-term (2 weeks) and long-term (6 months) effectiveness, adverse events, and need for surgery. RESULTS: The study included 211 patients (pseudocyst/walled-off pancreatic necrosis, 53%/47%). The FCSEMSs used were straight biliary (66%) or lumen-apposing (34%). Technical success was achieved in 97% of patients (95% confidence interval [CI], 93%-99%). Short-term- and long-term clinical success was obtained in 94% (95% CI, 89%-97%) and 85% (95% CI, 79%-89%) of patients, respectively. Adverse events occurred in 21% of patients (95% CI, 16%-27%): infection (11%), bleeding (7%), and stent migration and/or perforation (3%). By multivariate analysis, patient age (>58 years) and previous failed drainage were the most important factors associated with negative outcome. CONCLUSIONS: An FCSEMS is effective and safe for PFC drainage. Older patients with a history of unsuccessful drainage are more likely to fail EUS-guided drainage. The type of FCSEMS does not seem to influence patient outcome.

Facile Formation of Redox-Active Totally Organic Nanoparticles in Water by In Situ Reduction of Organic Precursors Stabilized through Aromatic-Aromatic Interactions by Aromatic Polyelectrolytes.

The formation of redox-active, totally organic nanoparticles in water is achieved following a strategy similar to that used to form metal nanoparticles. It is based on two fundamental concepts: i) complexation through aromatic-aromatic interactions of a water-soluble precursor aromatic molecule with polyelectrolytes bearing complementary charged aromatic rings, and ii) reduction of the precursor molecule to achieve stabilized nanoparticles. Thus, formazan nanoparticles are synthesized by reduction of a tetrazolium salt with ascorbic acid using polyelectrolytes bearing benzene sulfonate residues of high linear aromatic density, but cannot be formed in the presence of nonaromatic polyelectrolytes. The red colored nanoparticles are efficiently encapsulated in calcium alginate beads, showing macroscopic homogeneity. Bleaching kinetics with chlorine show linear rates on the order of tenths of milli-meters per minute. A linear behavior of the dependence of the rate of bleaching on the chlorine concentration is found, showing the potential of the nanoparticles for chlorine sensing.

A preliminary investigation on the relationship between gut microbiota and gene expressions in peripheral mononuclear cells of infants with autism spectrum disorders.

Fecal and blood samples of infants with autism spectrum disorders (ASD) and healthy infants were analyzed to investigate the association of altered gut microbiota and ASD development. 16S rRNA gene-based sequencing found that, unlike those of healthy infants, feces of ASD infants had significantly higher and lower abundance of genera Faecalibacterium and Blautia, respectively. Moreover, DNA microarray analysis of peripheral blood mononuclear cells (PBMC) detected more highly than low expressed genes in ASD infants than in healthy infants. Gene Ontology analysis revealed that differentially expressed genes between ASD and healthy infants were involved in interferon (IFN)-γ and type-I IFN signaling pathways. Finally, strong positive correlations between expression of IFN signaling-associated genes in PBMC and fecal abundance of Faecalibacterium were found. Our results strongly suggested that altered gut microbiota in infants resulted from ASD development and was associated with systemic immunity dysregulation, especially chronic inflammation.

Decreased level of phosphatidylcholine (16:0/20:4) in multiple myeloma cells compared to plasma cells: a single-cell MALDI-IMS approach.

Lipid metabolic changes under diseased conditions, particularly in solid tumors, are attracting increased attention. However, in non-solid tumors, including most hematopoietic tumors, lipid analyses are scarce. Multiple myeloma (MM) is a plasma cell disorder arising from bone marrow, and the lipid status of MM cells has not been reported yet. In this study, we analyzed flow cytometry-sorted single MM cells and normal plasma cells (NPCs) using matrix-assisted laser desorption/ionization-imaging mass spectrometry (MALDI-IMS), a two-dimensional label-free mass spectrometry technique for biomolecular analysis, to obtain specific lipid information. We isolated 1.31-5.77% of MM cells and 0.03-0.24% of NPCs using fluorescence-activated cell sorting (FACS). Analysis of purified cells using MALDI-IMS at the single-cell level revealed that the peak intensity and ion signals of phosphatidylcholine [PC (16:0/20:4) + H](+) at m/z 782.5 were significantly decreased in MM cells compared to NPCs. By examining particular cell populations rather than cell mixtures, our method can become a suitable tool for the analysis of rare cell populations at the single-cell level and advance the understanding of MM progression.

Portomesenteric vein thrombosis after laparoscopic sleeve gastrectomy.

INTRODUCTION: Portal and mesenteric vein thrombosis are relatively uncommon surgical complications, with difficult diagnosis and potentially severe consequences due to higher risk of bowel infarction. The purpose of this study was to present a series of patients who developed postoperative portal vein thrombosis after laparoscopic sleeve gastrectomy. METHODS: This is a retrospective analysis of patients who underwent sleeve gastrectomy between June 2005 and June 2011 who developed portal vein thrombosis. Demographic data, personal risk factors, family history of thrombosis, and postoperative results of thrombophilia study were analyzed in this study. RESULTS: A total of 1,713 laparoscopic sleeve gastrectomies were performed. Seventeen patients (1 %) developed portal vein thrombosis after surgery. Of the 17 patients, 16 were women, 8 had a history of smoking, 7 used oral contraceptives, and 2 had a family history of deep vein thrombosis of the lower limbs. All patients were discharged on the third day of surgery with no immediate complications. Symptoms presented at a median of 15 (range, 8-43) days after surgery with abdominal pain in most cases. One case required emergency laparotomy and splenectomy because of an active bleeding hematoma with massive portomesenteric vein thrombosis. In 11 cases, a thrombosis of the main portal vein was identified, in 15 the right portal branch was compromised, and in 10 the left portal branch. Eleven patients presented thrombosis of the superior mesenteric vein, and ten patients presented a concomitant thrombosis of the splenic vein. A massive PMVT was presented in six cases. Seven patients had a positive thrombophilia study. CONCLUSIONS: Portal vein thrombosis and/or mesenteric thrombosis are relatively uncommon complications in patients undergoing bariatric surgery. In this series, the portomesenteric vein thrombosis was the most common complication after LSG in a high-volume center.

A rapid method of screening lactic acid bacterial strains for conjugated linoleic acid production.

A more rapid and simpler method than those currently used was developed to screen conjugated linoleic acid (CLA)-producing bacteria isolated from cow milk. The screening of 500 strains was completed in 10 d and the screening efficiency was 10%. One strain resembling a Lactobacillus paracasei strain and two resembling L. helveticus strains converted free linoleic acid to total CLA ≥85%.

[Results of bariatric surgery. Experience over 18 years]. / Experiencia de 18 años de cirugía de obesidad en la Pontificia Universidad Católica de Chile.

BACKGROUND: Bariatric surgery is the gold-standard treatment for morbid obesity because it has low morbidity rates in high-volume centers and generates long term sustained weight loss. AIM: To describe our experience in bariatric surgery since the creation of our bariatric program in 1992. MATERIAL AND METHODS: Retrospective analysis of all patients subjected to bariatric surgery from 1992 to December 2010. Data was obtained from the electronic institutional registry. The Procedures per-formed were open and laparoscopic Roux-en-Y gastric bypass (BPGA and BPGL, respectively), laparoscopic adjustable gastric band (BGAL) and laparoscopic sleeve gastrectomy (GML). RESULTS: A total of 4943 procedures were performed, 768 (16%) BPGA, 2558 (52%) BPGL, 199 (4%) BGAL and 1418 (29%) GML. The number of procedures progressively increased, from 100 cases in 2000 to over 700 cases in 2008. Proportion of femóles and preoperative mean body mass Índex fluctuated between 69 and 79% and 35 and 43 kg/m², respectively, among the different procedures. Early and late complications fluctuated between Oto 1% (higher on BPGA) and 3 to 32.7% (higher on BGAL), respectively. The excess weight lost at five years was 76.1% in BPGA, 92.5% in BPGL and 53.7% in BGAL. The figure for GML at three years was 73.7%. CONCLUSIONS: The complication rates of this series of patients are similar to those reported in large series abroad. BPGL is still the most effective procedure; however GML is an attractive alternative for less obese patients.

Overexpression of 11ß-hydroxysteroid dehydrogenase type 1 in visceral adipose tissue and portal hypercortisolism in non-alcoholic fatty liver disease.

BACKGROUND: The enzyme 11ß-hydroxysteroid-dehydrogenase type 1 (11ß-HSD1) catalyses the reactivation of intracellular cortisol. We explored the potential role of 11ß-HSD1 overexpression in visceral adipose tissue (VAT) in non-alcoholic fatty liver disease (NAFLD) assessing sequential changes of enzyme expression, in hepatic and adipose tissue, and the occurrence of portal hypercortisolism in obese mice. 11ß-HSD1 expression was also assessed in tissues from obese patients undergoing bariatric surgery. METHODS: Peripheral and portal corticosterone levels and liver histology were assessed in ob/ob mice at two time points (8-12 weeks of age). 11ß-HSD1 tissue expression was assessed in by RT-pcr in ob/ob mice and in 49 morbidly obese patients. RESULTS: Portal corticosterone serum levels were higher in obese mice with a 26% decrease between 8 and 12 weeks of age (controls: 78.3 ± 19.7 ng/ml, 8-week-old ob/ob: 167.5 ± 14.5 ng/ml and 12-week-old ob/ob: 124.3 ± 28 ng/ml, P < 0.05). No significant differences were found in peripheral corticosterone serum levels. Expression of 11ß-HSD1 was lower in the liver [-45% at 8 weeks and -35% at 12-weeks (P = 0.0001)] and highly overexpressed in VAT in obese mice, compared to controls (128-fold higher in 8-week-old ob/ob and 41-fold higher in 12-week-old ob/ob, P < 0.01). No significant differences were seen in the expression of 11ß-HSD1 in subcutaneous adipose tissue. In multivariate analysis, human 11ß-HSD1 expression in VAT (OR: 1.385 ± 1.010-1.910) was associated with NAFLD. CONCLUSION: Murine NAFLD is associated with portal hypercortisolism and11ß-HSD1 overexpression in VAT. In humans, 11ß-HSD1 VAT expression was associated with the presence of NAFLD. Thus, local corticosteroid production in VAT may contribute to NAFLD pathogenesis.

Completely laparoscopic versus open gastrectomy for early and advanced gastric cancer: a matched cohort study.

INTRODUCTION: The application of laparoscopic gastric surgery has rapidly increased for the treatment of early gastric cancer. However, laparoscopic gastrectomy for advanced tumor remains controversial, particularly in terms of oncologic outcomes. This study was designed to compare 3-year survival of laparoscopic versus open curative gastrectomy in early and advanced gastric cancer. METHODS: This was a retrospective matched cohort study. We included patients between 2003 and 2010 with an R0 resection. A totally laparoscopic technique was used and D2 lymph node dissection was practiced routinely. We performed an intracorporeal hand-sewn esophagojejunostomy in all laparoscopic total gastrectomy cases. We matched all laparoscopic cases 1:1 with open cases according to TNM AJCC seventh edition. We used Mann-Whitney or t test and Chi-square test to compare both groups. Kaplan-Meier analysis with log-rank test was performed to compare survival. RESULTS: We included 31 open and 31 laparoscopic cases (mean age 63 ± 14 years; 66% males). Both groups were identical in type of gastrectomy (71% total and 29% subtotal). There were no statistical difference between laparoscopic and open groups in age, sex, N category, tumor location and size, histological differentiation, and T category (48% T1, 13% T2, 16% T3, and 23% T4 in both groups), with 48% early and 52% advanced tumors. The median number of resected lymph nodes was similar: 35 (23-53) for laparoscopic and 39 (23-45) for open cases (P = 0.81). The median follow-up was 50 months. The overall 3-year survival was 82% for laparoscopic surgery and 87% for the open surgery group (P = 0.56). There were no difference in 3-year survival for the laparoscopic versus the open surgery groups for advanced tumors (74 vs. 75%, P = 0.88), N+ tumors (73 vs. 73%, P = 0.99) and for the different AJCC stages (stage 1: 94 vs. 100%, stage 2: 89 vs. 82%, and stage 3: 50 vs. 50%, P = 0.32, 0.83, and 0.98 respectively). CONCLUSIONS: In this preliminary report, with 52% of advanced tumor, the 3-year overall and stage-by-stage survival was comparable for laparoscopic and open curative gastrectomy.

Immunogenicity of SARS-CoV-2 Trimeric Spike Protein Associated to Poly(I:C) Plus Alum.

The SARS-CoV-2 pandemic has had a social and economic impact worldwide, and vaccination is an efficient strategy for diminishing those damages. New adjuvant formulations are required for the high vaccine demands, especially adjuvant formulations that induce a Th1 phenotype. Herein we assess a vaccination strategy using a combination of Alum and polyinosinic:polycytidylic acid [Poly(I:C)] adjuvants plus the SARS-CoV-2 spike protein in a prefusion trimeric conformation by an intradermal (ID) route. We found high levels of IgG anti-spike antibodies in the serum by enzyme linked immunosorbent assay (ELISA) and high neutralizing titers against SARS-CoV-2 in vitro by neutralization assay, after two or three immunizations. By evaluating the production of IgG subtypes, as expected, we found that formulations containing Poly(I:C) induced IgG2a whereas Alum did not. The combination of these two adjuvants induced high levels of both IgG1 and IgG2a. In addition, cellular immune responses of CD4+ and CD8+ T cells producing interferon-gamma were equivalent, demonstrating that the Alum + Poly(I:C) combination supported a Th1 profile. Based on the high neutralizing titers, we evaluated B cells in the germinal centers, which are specific for receptor-binding domain (RBD) and spike, and observed that more positive B cells were induced upon the Alum + Poly(I:C) combination. Moreover, these B cells produced antibodies against both RBD and non-RBD sites. We also studied the impact of this vaccination preparation [spike protein with Alum + Poly(I:C)] in the lungs of mice challenged with inactivated SARS-CoV-2 virus. We found a production of IgG, but not IgA, and a reduction in neutrophil recruitment in the bronchoalveolar lavage fluid (BALF) of mice, suggesting that our immunization scheme reduced lung inflammation. Altogether, our data suggest that Alum and Poly(I:C) together is a possible adjuvant combination for vaccines against SARS-CoV-2 by the intradermal route.

Intradermal Immunization of SARS-CoV-2 Original Strain Trimeric Spike Protein Associated to CpG and AddaS03 Adjuvants, but Not MPL, Provide Strong Humoral and Cellular Response in Mice.

Despite the intramuscular route being the most used vaccination strategy against SARS-CoV-2, the intradermal route has been studied around the globe as a strong candidate for immunization against SARS-CoV-2. Adjuvants have shown to be essential vaccine components that are capable of driving robust immune responses and increasing the vaccination efficacy. In this work, our group aimed to develop a vaccination strategy for SARS-CoV-2 using a trimeric spike protein, by testing the best route with formulations containing the adjuvants AddaS03, CpG, MPL, Alum, or a combination of two of them. Our results showed that formulations that were made with AddaS03 or CpG alone or AddaS03 combined with CpG were able to induce high levels of IgG, IgG1, and IgG2a; high titers of neutralizing antibodies against SARS-CoV-2 original strain; and also induced high hypersensitivity during the challenge with Spike protein and a high level of IFN-γ producing CD4+ T-cells in mice. Altogether, those data indicate that AddaS03, CpG, or both combined may be used as adjuvants in vaccines for COVID-19.

Effect of environmental factors and influence of rumen and hindgut biogeography on bacterial communities in steers.

Feces from cattle production are considered important sources of bacterial contamination of food and the environment. Little is known about the combined effects of arctic temperatures and fodder tannins on rumen and hindgut bacterial populations. Individual rumen liquor and rectal fecal samples from donor steers fed either alfalfa silage or sainfoin (Onobrychis viciifolia Scop.) silage and water ad libitum were collected weekly on the first three sampling days and fortnightly afterwards. The daily ambient temperatures were registered and averaged to weekly mean temperatures. Steers fed sainfoin silage had lower (P < 0.05) concentrations of branched-chain volatile fatty acids (VFA) than those fed alfalfa silage. All VFA concentrations were higher (P < 0.001) in rumen liquor samples than in fecal samples. The interaction of sample type and diet showed a significant effect (P < 0.05) on the proportions of the bacterial community that were from the phyla Proteobacteria and Verrucomicrobia. Ambient temperature had an indirect effect (P < 0.05) on the phylum Firmicutes, as it affected its proportional balance. The bacterial population diversity in samples appeared to decrease concurrently with the ambient temperature. The phylum Firmicutes explained the first principal component at 64.83 and 42.58% of the total variance in rumen liquor and fecal samples, respectively. The sample type had a larger effect on bacterial communities than diet and temperature. Certain bacterial populations seemed to be better adapted than others to environmentally adverse conditions, such as less access time to nutrients due to higher motility and rate of passage of digesta caused by extreme temperatures, or antimicrobials such as tannins, possibly due to an influence of their biogeographical location within the gut.